Excavator tooth



Feb. 14, 1961 H; H. sMEDLEY 2,971,280

ExcAvAToR Toom Filed March ll, 1957 United States Patent v'2,911,280 ExcAvAroR Toorn `Harry H. smediey, 3142 Harrison si., oakland, Calif. Fried Mar. 11, 1957, ser. No. 645,048

1 claim. (ci. 31-142) The present invention relates to an improved digging tooth for removable attachment to the digging edges of excavating equipment such as ditching machines, scoop shovels, digging buckets and the like.

In excavating machinery it has become common practice to provide removable and sometimes adjustable teeth which serve as the cutting edge or edges of the equipment and a further refinement in the art has been the provision of replaceable teeth tips. Conventionally, teeth tips are reversible to provide maximum life thereof before replacement and are formed of hard long wearing metals to withstand continued driving through the earth.

In 'considering the requirements of excavating teeth and more 4particularly the tips therefor it will be appreciated that the tip must have a maximum strength possible for the size thereof as well as providing a maximum cutting ability i.e., providing a cutting edge requiring the least possible force to drive same into or through the earth. In addition the tip engagement with the tooth must be quite rigid and rin for any relative movement allowed will rapidly result in damage to one or the other because of thevtremendous stresses under which same. are often required to operate. -A further requirement is that despite the'rmness of tooth-tip engagement required these elements must be easily and rapidly separable for no matter how good the tip severe wear can be expected and not infrequent tip reversal or replacement is necessary.

Accordingly it is an object of the present invention to provide an improved excavator tooth having an engaging tip of maximum strength.

It is another object of the present invention to provide an excavator tooth with improved tip engagement for minimized tip drag and maximum tip strength.

It is a further object of the present invention to provide an improved tooth-tip engagement of maximized rigidity and facile detachment. r

It is yet another object of the present invention to provide an improved tip for an excavator tooth with maximized strength and minimized drag in cutting.

The invention possesses other objects and features of advantages, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention which is illustrated in the drawing accompanying and forming part of the specification. It is to be understood, however, that variations in the showing made by the said drawing and description may be adopted within the scope of the invention as set forth in the claim.

The invention is illustrated in the accompanying drawing, wherein:

Figure 1 is a perspective view of an improved tip for an excavator tooth in accordance with the present invention.

Figure 2 is an elevational view of the tip in engagement with an excavator tooth partially shown and in section.

7 Figure 3 is a plan view of the tip in engagement with an excavator tooth partially shown in section.

soV

Figure 4 is a perspective' view of an alternative tip embodiment also in accordance with the present invention.

Considering now the structural details of a preferred embodiment of the invention and referring lrst to Figure 1 of the drawings, there is shown therein a tooth tip 11 formed as a single integral element of a strong long wearing material such as molybdenum steel or the like suitablyv treated to enhance the strength thereof. The tip 11 comprises two main portions serving separate functions and thus herein separately denominated. The forward porf tion of the tip may be termed the blade 12 andV in axial alignment therewith and extending longiutdinaily rear-A ward from the blade is the shank 13. The shank portion of the tip serves the function of mounting the tip and while various shank configurations are known in the interests of maximum strength the herein illustrated shank 13 is formed as a solid billet of rectangular cross section; The shank 13 has a maximum width and height at the blade terminus and thus the shank sides 14 taper together away from the blade, as do the top and bottom 16.

In addition to the above-described shank configuration the rear end of the shank is deformed from planar for maximum strength and to facilitate tip removal, as set forth more fully below. The rear of the shank 13 has a central depression 17 which may be formed by a pair of like curved contours 18 and 19 extending rearwardly of the shank and transversely inward whereat they are joined by an indented straight end 21. There is further provided as a part of the shank 13 a plurality of ribs 22 disposed upon at least the bottom of the shank and zilso on the top if desired. These ribs 22 extend but slightly from the planar shank surfaces and are preferably disposed generally transversely of the shank for providing a gripping action with elements adapted to engage same.

As regards the tip blade 12 or forward portion of the tip 11, same is formed as a solid member and of the same material as the shank inasmuch as both comprise an integral element. In manufacture the tip is formed of one billet of metal so as to have maximum strength. The blade sides 23 are generally planar and are offset from the shank sides 14 at the juncture therewith by a fillet 24 displacing the blade sides inward of the shank sides. The blade top and bottom 26 are generally planar and taper evenly together away from the shank as do the blade sides 23 away from the fillet 24. At the forward edge of the blade there is formed a cutting edge 27 formed by an upward curve of the bottom into linear intersection with the top.

It is of particular note that the maximum width and maximum height of the tip hereinabove described occurs at the juncture of blade and shank. Also, it will be appreciated that inasmuch as the tip comprises a single element the denomination of portions thereof as blade and shank is somewhat arbitrary so that in order to further define these terms the shank is ta'ken as the rear tip portion adapted to fit wholly within a tooth socket. With this definition of the tip shank it follows that the tip blade extending from a tooth body has a decreasing height and width away from the same, for reasons set out below.

The excavating tooth 31 of the present invention includes, in additon to the removable tip described above, a tooth body 32 as seen in Figures 2 and 3. The tooth body is preferably formed as a single unit having a socket 33 of rectangular cross section formed therein at the outer end thereof. The body socket 33 is par tially defined by upper and lower jaws 341 and 36, respectively, which taper away from the socket edges and the o upper jaw 34 extends beyond the lower jaw 36. The

socket has a rectangular cross section tapering together away from the opening thereof at substantially the same A 2,971,280 Y y i taper as .the tipfslianksqthat vthe latter isadapted to lit thereininintirnate contact with the socket walls. Similarly the upper jaw 34 is adapted to engage the tip blade to impart maximum strength thereto. The upper jaw Qigtheocketwi-ll be',y seen in -.F-igurel 2 to extend beyond the blade-Shank juncture.- Of; thetip S asf t0 bean upon the upper surface of the blade and blade insertion is possible-because ofthef ribs on the shank underysurface allowingtheftip,toprslide past .thel socket upper jaw. With the maximumtip crossvsection located at the outer edge o,fthe ,lowerrjawl 36h11@ the, upper jaw bearing upon the upper,l blade surfaceathetorque or bendingmoment on the;` tip during use is adequatelyl compensated for so that maximum tip strength isprovided.

.Y In addition to, theforegoingtooth-body configuration, the-upperjaw34zthereof is reduced in width from the main bodysize and; curvedoutward thereto in alignment with ythe 4tip4 llet 24 so that vno drag is produced by the uppergjaw4 duringuse-ofthe` toothA in excavating. At the rear of 1 the tooth body there are provided a pair of rearwardly extendingearsj which provide means for mounting the tooth upon equipment such as an excavator as byl welding thereto',

Provision .is made for rapid and facile tip removal as for reversalY or replacement by forming a transverse y perturef-Sthrough the :tooth body near the inner socket end .andcentrally thereof, as shown in Figure 3. This aperture partiallykoverlays the rear tip edge at the depression 17 thereof when the tip is fully inserted in the socketsothat a tapered pin may be inserted in the aperture 3,8 yandrupon being rdriven further therein bears onlthetip tovforce Vsameoutol the socket. The advantage of some form. oftiprelease will be understood from noting'thatnormal tooth use may tend to further seat the; tip'in-thesocket so that a very tight lit results which can only be foreably separated.

It will be seen from Figures 2 and 3 that the lower toothsocketedge or jaw 36 ysubstantially aligns with the juncture fof blade` and shank on the tip when the tip is inserted inthe tooth socket and that the blade size steadily decreases away froml the tooth body. This is of importance in that a maximized tip cutting action is afforded thereby. Inasmuchk as in excavating and material handling vas herein contemplated rather deep cuts are common, the tipblade is often employed in its entirety for cutting, i.e., the depth of cut approaches or-equalsthe blade length. It is thus advantageous to reduce or eliminate the drag or resistance of the tip portion adjacent the tooth body. To this end the tip of the present invent provides a particular configuration wherein the blade proper extends at least to the tooth body without structural enlargements or protuberances which resist the passage of the blade through Va material such as earth being handled. At the Sametime the tip strength is maximized by location of maximum tip height and width at a position of great stress, and by the upper jaw contacting overhang.

A further tip embodimentV 41, as shown inV Figure 4, is like the embodiment of Figure 1 with the exception of the blade taper which ismade considerable as regards the blade sides 42. In this instance a narrow blade edge 43 is provided for particular applications where a somewhat pointed blade conguration is advantageous. The blade structure insofar as maximum width and height location remains the same as the embodiment of Figure 1 and thus the blade 41 retains all of theadvam tages set out above.

What is claimed is:

An excavator tooth comprising a rigid tip havingan integral blade and shank with maximum tip,;widtl 1gand height at the blad shank juncture; and an; integral rigid body having a tapered socket adapted to receive and envelop all of said tip shank and including a rigid upper jaw having a portion extending outwardly of said socket into contact with at least a part of said tip blade and said portion having tapered sides extending no further than the blade sides, and the maximum,width.of,the opposed edges of said blade having a lesserwidth than thatof said body and' merging therewith in asubstantially continuous pattern.

References Cited inthe le of this.v patent UNITED STATES PATENTS 

